Azo dyes are widely used in textile, fiber, cosmetic, leather, paint and printing industries.
Besides their characteristic coloring function, azo compounds are reported as antibacterial, antiviral,
antifungal and cytotoxic agents. They have the ability to be used as drug carriers, either by acting as a
‘cargo’ that entrap therapeutic agents or by prodrug approach. The drug is released by internal or external
stimuli in the region of interest, as observed in colon-targeted drug delivery. Besides drug-like
and drug carrier properties, a number of azo dyes are used in cellular staining to visualize cellular
components and metabolic processes. However, the biological significance of azo compounds, especially
in cancer chemotherapy, is still in its infancy. This may be linked to early findings that declared
azo compounds as one of the possible causes of cancer and mutagenesis. Currently, researchers are
screening the aromatic azo compounds for their potential biomedical use, including cancer diagnosis
and therapy. In this review, we highlight the medical applications of azo compounds, particularly related
to cancer research. The biomedical significance of cis-trans interchange and negative implications
of azo compounds are also discussed in brief.